Hi,
i am using the TJA1050 in our products and replaced it with the TJA1051 because of this line in the datasheet:
Today i was working on another project and came across the TJA1051 again and saw this:
with Vio = VCC this means that VIH = 0,7*5=3,5V
From the datasheet TJA1050:
So in other words: TJA1050 and TJA1051 are not compatible on controller side.
Somehow i missed that part and now our products are running with the TJA1051 (not the /3 variant) directly connected to a Kinetis MK22, which has 3.3V outputs.
And it just works fine.
So my question is: am i lucky that it works?
Or is this a combination of the five volt tolerant MK22 pins and the internal pull up from the TJA1051 on TXD?
I am not sure on which way to go now...
Accept the fact that this is working or redesign all of our products?
Thanks in advance!
Greetings
Jörn
1:You can test the TX pin value during TJA1051 work.
2: change it into TJA1051/3,it should be no more risk.